From cad7ddfdc02df0c36e44aca9e3cb6e29769e0f7f Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 27 Feb 2014 23:02:43 +0000 Subject: cns3xxx: ethernet - clean up tx descs only when needed We already clean up tx descriptors in the napi eth_poll() function so it would likely be rare to run out of available descriptors in eth_xmit. Thus we can clean them up only when needed and return busy only when we still don't have enough. Signed-off-by: Tim Harvey git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39762 3c298f89-4303-0410-b956-a3cf2f4a3e73 --- .../cns3xxx/files/drivers/net/ethernet/cavium/cns3xxx_eth.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'target/linux/cns3xxx') diff --git a/target/linux/cns3xxx/files/drivers/net/ethernet/cavium/cns3xxx_eth.c b/target/linux/cns3xxx/files/drivers/net/ethernet/cavium/cns3xxx_eth.c index bbbbf5c091..9692d47994 100644 --- a/target/linux/cns3xxx/files/drivers/net/ethernet/cavium/cns3xxx_eth.c +++ b/target/linux/cns3xxx/files/drivers/net/ethernet/cavium/cns3xxx_eth.c @@ -583,7 +583,7 @@ static void eth_check_num_used(struct _tx_ring *tx_ring) } } -static void eth_complete_tx(struct sw *sw) +static int eth_complete_tx(struct sw *sw) { struct _tx_ring *tx_ring = &sw->tx_ring; struct tx_desc *desc; @@ -615,6 +615,8 @@ static void eth_complete_tx(struct sw *sw) tx_ring->free_index = index; tx_ring->num_used -= i; eth_check_num_used(tx_ring); + + return TX_DESCS - tx_ring->num_used; } static int eth_poll(struct napi_struct *napi, int budget) @@ -776,11 +778,13 @@ static int eth_xmit(struct sk_buff *skb, struct net_device *dev) skb_walk_frags(skb, skb1) nr_desc++; - eth_schedule_poll(sw); spin_lock_bh(&tx_lock); if ((tx_ring->num_used + nr_desc + 1) >= TX_DESCS) { - spin_unlock_bh(&tx_lock); - return NETDEV_TX_BUSY; + /* clean up tx descriptors when needed */ + if (eth_complete_tx(sw) < nr_desc) { + spin_unlock_bh(&tx_lock); + return NETDEV_TX_BUSY; + } } index = index0 = tx_ring->cur_index; -- cgit v1.2.3